Deferred Charges and Other Assets, net - Schedule of deferred charges and other assets, net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Leasing	$ 202,628		$ 202,628		$ 226,885
Intangible assets:
In-place lease values	85,196		85,196		94,966
Leasing commissions and legal costs	21,452		21,452		23,508
Above-market leases	64,814		64,814		140,889
Deferred tax assets	30,999		30,999		32,197
Deferred compensation plan assets	52,099		52,099		45,857
Other assets	62,838		62,838		75,497
Deferred charges and other assets, gross	520,026		520,026		639,799
Less accumulated amortization	(219,883)		(219,883)		(249,396)
Deferred charges and other assets, net	300,143		300,143		390,403
In-place lease values, leasing commissions and legal costs
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization for intangible assets	66,985		66,985		$ 72,286
Amortization expense for intangible assets	$ 3,320	$ 3,552	$ 6,525	$ 7,390